Chrysler 300/300 Touring/300C, Dodge Magnum. Manual - part 2349

DIAGNOSIS AND TESTING

A/C COMPRESSOR

When investigating an A/C system related noise, you must first know the conditions under which the noise occurs.
These conditions include: weather, vehicle speed, transmission in gear or neutral, engine speed, engine tempera-
ture, and any other special conditions. Noises that develop during A/C operation can often be misleading. For exam-
ple: What sounds like a failed front engine bearing or connecting rod, may be caused by loose bolts, nuts, mounting
brackets or a loose compressor clutch assembly.

Drive belts are speed sensitive. At different engine speeds and depending upon drive belt tension, drive belts can
develop noises that are mistaken for an A/C compressor noise. Improper drive belt tension can cause a misleading
noise when the compressor clutch is engaged, which may not occur when the compressor clutch is disengaged.
Check the accessory drive belt condition and tension as described in Cooling before beginning this procedure.

1. Select a quiet area for testing. Duplicate the complaint conditions as much as possible. Turn the A/C compressor

On and Off several times to clearly identify the compressor noise. Listen to the A/C compressor while the clutch
is engaged and disengaged. Probe the A/C compressor with an engine stethoscope or a long screwdriver with
the handle held to your ear to better localize the source of the noise.

2. Loosen all of the compressor mounting hardware and retighten. Check the compressor clutch retainer. Be certain

that the clutch field coil is mounted securely to the A/C compressor, and that the clutch plate and pulley are
properly aligned and have the correct air gap (Refer to 24 - HEATING & AIR CONDITIONING/CONTROLS/
CLUTCH-A/C COMPRESSOR - INSTALLATION).

3. To duplicate high-ambient temperature conditions (high head pressure), restrict the air flow through the A/C con-

denser. Install a manifold gauge set or a scan tool to be certain that the discharge pressure does not exceed
2760 kPa (400 psi).

4. Check the refrigerant system plumbing for incorrect routing, rubbing or interference, which can cause unusual

noises. Also check the refrigerant lines and hoses for kinks or sharp bends that will restrict refrigerant flow, which
can cause noises (Refer to 24 - HEATING & AIR CONDITIONING/PLUMBING - DESCRIPTION - REFRIGER-
ANT LINES).

5. If the noise is from opening and closing of the high pressure relief valve, recover, evacuate and recharge the

refrigerant system (Refer to 24 - HEATING & AIR CONDITIONING/PLUMBING - STANDARD PROCEDURE -
REFRIGERANT SYSTEM RECOVERY), (Refer to 24 - HEATING & AIR CONDITIONING/PLUMBING - STAN-
DARD PROCEDURE - REFRIGERANT SYSTEM EVACUATE) and (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - STANDARD PROCEDURE - REFRIGERANT SYSTEM CHARGE).

6. If the high pressure relief valve still does not seat properly, replace the A/C compressor (Refer to 24 - HEATING

& AIR CONDITIONING/PLUMBING/COMPRESSOR-A/C - REMOVAL).

REMOVAL

2.7L ENGINE

WARNING: Refer to the applicable warnings and cautions for this system before performing the following
operation (Refer to 24 - HEATING & AIR CONDITIONING/PLUMBING - WARNINGS) and (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING - CAUTIONS). Failure to follow the warnings and cautions could result
in possible personal injury or death.

NOTE: The A/C compressor may be removed and repositioned without disconnecting the refrigerant lines or
discharging the refrigerant system. Discharging is not necessary if servicing the compressor clutch, clutch
field coil, engine, engine cylinder head or the generator.

NOTE: If an internal failure of the A/C compressor has occurred, the receiver/drier must be replaced.

24 - 430

PLUMBING

1. Recover the refrigerant from the refrigerant system

(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING

STANDARD

PROCEDURE

REFRIGERANT SYSTEM RECOVERY).

2. Disconnect and isolate the negative battery cable.

3. Remove the air cleaner housing (Refer to 9 -

ENGINE/AIR

INTAKE

SYSTEM/AIR

CLEANER

HOUSING - REMOVAL).

4. Remove the acessory drive belt (Refer to 7 -

COOLING/ACCESSORY

DRIVE/BELTS-DRIVE

REMOVAL).

5. Disconnect the wire harness connector from the

compressor clutch field coil connector (1).

6. Remove the nuts (2) that secure the A/C suction

line (3) and A/C discharge line (4) to the A/C com-
pressor (5).

7. Disconnect the suction and discharge lines from

the A/C compressor and remove and discard the
dual plane seals.

8. Install plugs in, or tape over all of the opened refrigerant line fittings and the compressor ports.

9. Raise and support the vehicle.

10. Remove the front end splash shield (Refer to 23 -

BODY/EXTERIOR/FRONT

END

SPLASH

SHIELDS - REMOVAL).

NOTE: The bolt that secures the transmission
cooler line bracket to the A/C compressor cannot
be fully removed until the compressor is posi-
tioned away from the cylinder block.

11. Fully loosen the bolt (3) that secures the auto-

matic transmission cooler line bracket (4) and A/C
compressor (5) to the cylinder block (6).

12. Support the A/C compressor and remove the bolts

(1 and 2) that secure the compressor to the cylin-
der block.

CAUTION: Use care not to deform or damage the
automatic transmission cooler lines and retaining
bracket when repositioning the A/C compressor.

13. Position the A/C compressor to gain clearance to the remove the bolt that secures the automatic transmission

cooler line bracket to the compressor.

14. Remove the bolt that secures the automatic transmission cooler line bracket to the A/C compressor and remove

the compressor from the engine compartment.

3.0L ENGINE

PLUMBING

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NOTE: If an internal failure of the A/C compressor has occurred, the receiver/drier must be replaced.

1. Recover the refrigerant from the refrigerant system

(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING

STANDARD

PROCEDURE

REFRIGERANT SYSTEM RECOVERY).

2. Disconnect and isolate the negative battery cable.

3. Remove the air cleaner housing (Refer to 9 -

ENGINE/AIR

INTAKE

SYSTEM/AIR

CLEANER

HOUSING - REMOVAL).

4. Remove the accessory drive belt (Refer to 7 -

COOLING/ACCESSORY

DRIVE/BELTS-DRIVE

REMOVAL).

5. Disconnect the engine wire harness from the com-

pressor clutch field coil connector (1).

6. Remove the nuts (2) that secure the A/C suction

line (3) and A/C discharge line (4) to the A/C com-
pressor (5).

7. Disconnect the suction and discharge lines from

the A/C compressor and remove and discard the
dual plane seals.

8. Install plugs in, or tape over all of the opened refrigerant line fittings and the compressor ports.

9. Raise and support the vehicle.

10. Remove the front end splash shield (Refer to 23 -

BODY/EXTERIOR/FRONT

END

SPLASH

SHIELDS - REMOVAL).

11. Support the A/C compressor (4) and remove the

three bolts (1and 2) that secure the compressor
and the automatic transmission cooler line bracket
(3) to the cylinder block (5).

12. Position the cooler lines out of the way and

remove the A/C compressor from the engine
compartment.

3.5L ENGINE

NOTE: If an internal failure of the A/C compressor has occurred, the receiver/drier must be replaced.

24 - 432

PLUMBING

1. Recover the refrigerant from the refrigerant system

(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING

STANDARD

PROCEDURE

REFRIGERANT SYSTEM RECOVERY).

2. Disconnect and isolate the negative battery cable.

3. Remove the air cleaner housing (Refer to 9 -

ENGINE/AIR

INTAKE

SYSTEM/AIR

CLEANER

HOUSING - REMOVAL).

4. Remove the accessory drive belt (Refer to 7 -

COOLING/ACCESSORY

DRIVE/BELTS-DRIVE

REMOVAL).

5. Disconnect the engine wire harness from the com-

pressor clutch field coil connector (1).

6. Remove the nuts (2) that secure the A/C suction

line (3) and A/C discharge line (4) to the A/C com-
pressor (5).

7. Disconnect the suction and discharge lines from

the A/C compressor and remove and discard the
dual plane seals.

8. Install plugs in, or tape over all of the opened refrigerant line fittings and the compressor ports.

9. Raise and support the vehicle.

10. Remove the front end splash shield (Refer to 23 -

BODY/EXTERIOR/FRONT

END

SPLASH

SHIELDS - REMOVAL).

NOTE: The bolt that secures the transmission
cooler line bracket to the A/C compressor cannot
be fully removed until the compressor is posi-
tioned away from the cylinder block.

11. Fully loosen the bolt (3) that secures the auto-

matic transmission cooler line bracket (4) and A/C
compressor (5) to the cylinder block (6).

12. Support the A/C compressor and remove the bolts

(1 and 2) that secure the compressor to the cylin-
der block.

CAUTION: Use care not to deform or damage the
automatic transmission cooler lines and retaining
bracket when repositioning the A/C compressor.

13. Position the A/C compressor to gain clearance to the remove the bolt that secures the automatic transmission

cooler line bracket to the compressor.

14. Remove the bolt that secures the automatic transmission cooler line bracket to the A/C compressor and remove

the compressor from the engine compartment.

5.7L/6.1L ENGINES

PLUMBING

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